The objective of this randomized clinical trial is to address the relative effectiveness of three distinct treatment strategies for children with comorbid ADHD and reading difficulties (RD). Despite the commonly observed overlap of ADHD and RD, little research has been conducted to determine whether established disorder-specific interventions, alone or in combination, are effective for addressing the needs of children with these co-occurring difficulties. A sample of 288 elementary school children with ADHD and RD will be recruited across two sites and randomly assigned to three groups: (a) disorder-specific ADHD treatment (careful medication management + behavioral parent training), (b) disorder-specific RD treatment (highly intensive reading instruction), or (c) the combination of ADHD and RD treatments. Pre- and post- intervention measures will be used to evaluate a variety of behavioral and academic outcomes including ADHD symptomatology and word reading abilities. We address 3 specific aims: Aim 1 (Disorder-Specific Treatment) involves the examination of the relative benefits of providing either disorder-specific ADHD or RD treatment to children with comorbid ADHD/RD. Aim 2 (Combined Treatment) addresses whether intensive reading intervention + careful medication management and behavioral intervention is more effective than either of these interventions alone for improving word reading and decreasing ADHD symptomatology in children with ADHD and RD. Aim 3 (Moderators) involves the examination of variables that may moderate disorder- specific treatment response in children with comorbid ADHD and RD. We expect that outcomes may be moderated by variables such as demographic variables (e.g., SES) and severity of ADHD and reading impairment. PUBLIC HEALTH RELEVANCE: The objective of this randomized clinical trial is to address unanswered questions about the relative effectiveness of treatments for children with both ADHD and significant reading difficulties (RD), a commonly observed comorbidity. We propose 3 specific aims related to attentional and word reading outcomes for students with comorbid ADHD and RD when provided with either (a) disorder-specific ADHD treatment (medication + parent training), (b) disorder-specific RD treatment (intensive direct reading instruction), or (c) the combination of ADHD and RD treatment. The first two aims address the relative benefits of providing either disorder-specific ADHD or RD treatment alone (Aim 1) and providing the combined treatment (Aim 2), while the third aim examines the effects of moderator variables on the disorder-specific treatment outcomes.